1. Field of the Invention
The present invention relates to a sandblasting cabinet for sandblasting inscriptions and plastified ornaments on workpieces, especially those made of stone, glass, and wood, with a mechanically guided and driven, adjustable blasting nozzle which is guided in X-Y directions over the workpiece surfaces which are to be treated.
2. Description of the Related Art
Known automatic sandblasting devices used in the stone industry are built in a manner such that a rectangular working field which is limited by several final switches is worked off and with that the blasting is done.
These devices do not provide for automatic repetitions of these working fields and must then be stopped manually when a sufficient depth of the inscription or the ornamentation in the workpiece has been reached.
Also, the use of time relays or counters, which work from high to zero where the unit stops after achieving a predetermined number of field repetitions and when having reached a predetermined depth, are already known.
All of these known devices have the disadvantage that only one rectangular working field can be treated and, independent from the space between proper lines and ornaments which should be treated, the whole space of the workpiece is treated.
By this working method, high air pressure and blasting material consumption per piece is necessary because the blasting time is unnecessarily multiplied.
Furthermore, there are no known sandblasting units which have sufficient sound-absorbing properties in view of the air flow in the cabinet to satisfy health regulations.
The known units also do not allow movement of the blasting lance without creating an opening or fissure in the rubber seal where noise and blasting material can escape. There are also no commercially available sandblasting cabinets which are manufactured with a profile frame construction which is lined with noise absorbing material.
Blasting material recovery, if existent, is inefficient. All known devices have an abrasion problem which results in wear between movable parts. Also, known dust extraction systems have disadvantages. For example, not only is blasting material which was still usable removed, but also the workers view is obstructed by particles which spread all around. This tends to diminish the quality of work.